JP4974322B2 - Full-color image forming device - Google Patents

Description

  The present invention relates to a toner used as a developer for developing an electrostatic charge image in electrophotography, electrostatic recording, electrostatic printing, and the like, a manufacturing method thereof, and an image forming method using the toner. Further, the present invention relates to an electrophotographic toner used in an electrophotographic developing apparatus such as a copying machine, a laser printer, and a plain paper fax machine using a direct or indirect electrophotographic developing system, and an image forming method. Further, the present invention relates to an electrophotographic toner used in an electrophotographic developing apparatus such as a full-color copying machine, a full-color laser printer, and a full-color plain paper fax machine using a direct or indirect electrophotographic multicolor image developing method, and an image forming method.

  Conventionally, a latent image formed electrically or magnetically in an electrophotographic apparatus, an electrostatic recording apparatus or the like has been visualized with toner. For example, in electrophotography, an electrostatic charge image (latent image) is formed on a photoreceptor, and then the latent image is developed with toner to form a toner image. The toner image is usually transferred onto a transfer material such as paper, and then fixed onto the transfer material such as paper by a method such as heating. Further, the photosensitive member is cleaned by a cleaning member in order to form a latent image again. The toner used for developing an electrostatic image is generally colored particles containing a colorant, a charge control agent, and other additives in a toner binder. There is chemical toner.

  In recent years, there has been an increasing demand for chemical toners in order to obtain high-quality and high-quality images. The chemical toner manufacturing method can make the particle shape uniform, such as a spherical shape, and can have a small particle size and a sharp particle size distribution. In particular, by making the particle shape spherical, it is possible to improve transfer efficiency, reduce toner consumption, obtain a high-quality image with no missing image, and reduce running cost. If the transfer efficiency is very good, there is no need for a cleaning unit for removing untransferred toner from the photoreceptor or transfer medium, which has the advantages of reducing the size and cost of the equipment and eliminating waste toner. Because.

  At present, various chemical toner production methods have been devised. For example, a toner production method using a suspension polymerization method, an emulsion polymerization aggregation method, or a polymer dissolution suspension method has been studied. There is a problem that the fixing property is lowered and a poor image is obtained. In particular, in fixing, the fixing property of the halftone part is deteriorated. This is because the toner adhering to the halftone portion has a small amount of toner, so that the toner transferred to the concave portion on the transfer material has an extremely small amount of heat given from the fixing roller and is likely to cause offset development. Because.

  In particular, in an image forming system using an intermediate transfer body, when toner transferability is low, a part of the toner image is not transferred, and voids and transfer dust occur. Furthermore, in the case of a color image, the toner layers of 1 to 3 colors are laminated and adhered on the intermediate transfer member, so that the image quality is greatly deteriorated due to transfer failure, and on the recording medium. When fixing the transferred toner layer, it is difficult to apply a sufficient amount of heat to the entire toner layer, and cold offset, smear resistance, and color developability are deteriorated.

  So far, for example, as described in Patent Documents 1 and 2, there have been many disclosures that have improved color reproducibility and color developability by using specific colorants. In addition to this, depending on the presence of a colorant such as a pigment, it may cause deterioration of fixability in a high temperature range.

  Patent Document 3 includes a specific binder resin and a charge control agent, and improves the fixing property and transparency of intermediate colors by defining the presence state of the charge control agent, the endothermic peak temperature of DSC measurement, and the storage elastic modulus. However, since it is necessary to use a specific charge control agent, it is not general-purpose.

JP 2003-31680 A JP 2004-117649 A JP 2003-280265 A

In a full-color image forming apparatus that is fixed by a heat fixing method, in a multi-color toner layer formed on a recording medium, the heat present from the lower layer is less likely to be transferred to the toner layer, and a cold offset occurs. Or smear resistance worsens. Further, since the toners cannot be melted, the color mixing property is deteriorated, and the color reproducibility and color developability of intermediate colors are deteriorated. In particular, it greatly affects the transparency and color development on the OHP sheet.
An object of the present invention is a full-color image forming apparatus, which has both low-temperature fixability and hot offset resistance, even for an image composed of multicolored color toners, and has excellent color reproducibility and color mixing with excellent color reproducibility. It is to provide a high full color image forming apparatus.

  As a result of repeated investigations on the above problems, the present inventors have defined the colorant abundance ratio (hereinafter referred to as the surface colorant abundance ratio) on the surface of the toner particles of the full-color toner and formed on the recording medium. It has been found that the above-mentioned problems can be solved by using an image forming apparatus in which the full color toner having the highest surface colorant abundance ratio among the multi-color toner layers is the upper layer.

  In general, a colorant such as a pigment present on the surface of toner particles (hereinafter, a case of a pigment as a typical example of a colorant) inhibits low-temperature fixing. Low temperature fixability works favorably. When an unfixed image in which multicolored color toners are laminated is heat-fixed in the fixing section, the toner present in the lower layer is less likely to conduct heat and the fixability deteriorates, but the surface colorant of the toner in the uppermost layer By maintaining the abundance ratio optimally and by making the surface colorant abundance ratio of the lower layer toner smaller than the surface colorant abundance ratio of the toner particles of the upper layer toner, the toners can be melted with a small amount of heat, As a result, it is considered that color reproducibility and color developability can be improved.

That is, the problems of the present invention are solved by the following technical means and methods.
(1) “Developing means for developing an electrostatic latent image formed sequentially with a plurality of full-color toners containing at least a binder resin and a colorant to form an image, and forming the formed image on a recording medium A full-color image forming apparatus having a fixing means for fixing an image on a recording medium after being transferred, of full-color toner formed so as to be superimposed on the recording medium, having the highest surface colorant abundance ratio There is an upper layer higher full-color toner, the amount present surface colorant ratio, Ri 1.3 to 2.0 der, surface colorant abundance ratio of each color toner is Ru der 0.9-2.0 Full-color image forming apparatus characterized by
(2) “ The full-color image forming apparatus according to (1) above, wherein the colorant contents of the plurality of full-color toners are each 1 to 15% by weight ”;
(3) "colorant content of said plurality of full-color toners, the you, characterized in that each identical first (1) or (2) full-color image forming apparatus according to claim"
( 4 ) "The full color image forming apparatus according to any one of (1) to (3) above, wherein the toner having the highest surface colorant abundance ratio is a yellow toner",
( 5 ) “The full-color toner is composed of yellow, magenta, and cyan toners, and the respective surface colorant abundance ratios (Py, Pm, Pc) are Py> Pm, Py> Pc, The full-color image forming apparatus according to any one of Items (1) to (4) ”, ( 6 )“ Surface colorant abundance ratio Pm of the magenta toner is 1.2 to 1.7, and the cyan The surface colorant abundance ratio Pc of the toner is 1.0 to 1.7, the surface colorant abundance ratio Py> Pm of the yellow toner, and Py> Pc, ( 5 ) The full-color image forming apparatus according to the item ",
( 7 ) Any one of the above items (1) to ( 6 ), wherein the colorant of the toner having the highest surface colorant abundance ratio is an azo pigment or a quinacridone pigment A full-color image forming apparatus described in "
( 8 ) “The toner base particle of the toner is a toner obtained by dispersing an organic solvent containing a toner material in an aqueous medium and then removing the organic solvent. ) To ( 7 ), a full color image forming apparatus ”,
( 9 ) “The toner base particles of the toner have a polymer having at least a site capable of reacting with a compound having an active hydrogen group and an active hydrogen group, and an organic solvent in which a colorant is dissolved or dispersed is dispersed in an aqueous medium. The toner obtained by removing, washing and drying the organic solvent after reacting or reacting the compound having the active hydrogen group and the polymer having a site capable of reacting with the active hydrogen group. The full-color image forming apparatus according to item ( 8 ), wherein:
( 10 ) “The volume average particle diameter (Dv) of the toner particles of the toner is 3.0 to 7.0 μm, and the ratio of the volume average particle diameter (Dv) to the number average particle diameter (Dn) (Dv / Dn) is a full color image forming apparatus according to any one of items (1) to ( 9 ), wherein the value is 1.25 or less,
( 11 ) "The full-color image forming apparatus according to any one of (1) to ( 10 ), wherein an average circularity of toner particles of the toner is 0.94 to 0.99". ,
( 12 ) “The recording medium on which the unfixed image has been formed is provided with a heating body having a heating element, a film in contact with the heating body, and a pressure member in pressure contact with the heating body through the film. The full-color image according to any one of (1) to ( 11 ), wherein the fixing unit includes a fixing unit that heat-fixes the unfixed image by passing between the film and the pressure member. Forming device ",
( 13 ) "The recording medium on which the unfixed image is formed is made of a magnetic metal and heated by electromagnetic induction, a fixing roller arranged in parallel with the heating roller, the heating roller, and the An endless belt-like toner heating medium that is stretched between the fixing roller and heated by the heating roller and rotated by the rollers, and is pressed against the fixing roller through the toner heating medium, and The fixing means having a pressure roller that rotates in the forward direction with respect to the rotational movement direction of the toner heating medium to form a fixing nip portion is passed between the toner heating medium and the pressure roller, and the undetermined The full-color image forming apparatus according to any one of (1) to ( 12 ), wherein the received image is heat-fixed,
( 14 ) “An electrostatic latent image formed sequentially with a plurality of full-color toners containing at least a binder resin and a colorant is developed to form an image, and the formed image is transferred onto a recording medium. A full color image forming method for fixing an image on a subsequent recording medium, wherein the full color toner having the highest surface colorant abundance ratio among the full color toners formed to be superimposed on the recording medium is the upper layer to Yes, the surface colorant abundance ratio is 1.3 to 2.0 der is, a surface colorant abundance ratio of each color toner, characterized in 0.9-2.0 der Rukoto Full color image forming method ",
(15) " The full-color image forming method according to (14) above, wherein the colorant content of each of the plurality of full-color toners is 1 to 15% by weight ",
(16) " The full-color image forming method according to (14) or (15) above, wherein the colorant contents of the plurality of full-color toners are the same ",
( 17 ) “A recording medium comprising a toner image formed by sequentially developing an electrostatic latent image formed on an electrostatic latent image carrier with a plurality of full-color toners containing at least a binder resin and a colorant. A full-color toner kit comprising at least yellow, magenta, and cyan toners, which is used in a fixing device for fixing a toner image on a recording medium after being transferred onto the recording medium, and the toner image is superimposed on the recording medium. of the formed full-color toner as the highest color toner surface colorant abundance ratio is in the upper layer, the surface colorant abundance ratio, Ri 1.3 to 2.0 der, each full color toner surface colorant abundance ratio, full-color toner Kid, wherein 0.9-2.0 der Rukoto "
(18) “ The full-color toner kit according to (17), wherein the colorant contents of the plurality of full-color toners are each 1 to 15% by weight ”,
(19) The “ full color toner kit according to item (17) or (18), wherein the colorant contents of the plurality of full color toners are the same ”.

  According to the present invention, in a full-color image forming apparatus using an intermediate transfer body, even an image made of multi-colored toners has excellent low-temperature fixability, hot offset resistance, and color development properties at the same time. The extremely excellent effect of providing a full-color image forming apparatus capable of obtaining a high-quality full-color image with high reproducibility is exhibited.

Next, an embodiment of the present invention will be described.
Here, as for the toner, the manufacturing method and material of the developer used in the present invention, and the overall system relating to the electrophotographic process, known ones can be used if the conditions are satisfied.

<Surface colorant abundance ratio>
The surface colorant abundance ratio of the toner in the present invention, the total colorant amount contained in the toner particles to (to toner parts by weight), colorants amount present near the surface of the toner particles (to toner near the surface parts represented by), provided that pigment is a surface colorant abundance ratio of 1 the state of being uniformly dispersed in the toner particles. Surface colorant abundance ratio is unevenly distributed inside the smaller than 1, it can be said that a high surface uneven distribution of larger than 1. Here, the vicinity of the surface of the toner in the present invention refers to a region of about 1.0 μm from the outermost surface of the toner particles to the inside of the toner particles.

  The total amount of colorant contained in the toner is such that the colorant such as a pigment is sufficiently dispersed in the binder resin at the time of toner production and can be sufficiently contained without loss in the toner particles. If there is, it is easy to obtain from the prescription amount. Further, even if the toner has an unknown colorant amount, the colorant amount can be determined by various methods, and the method is not particularly limited. For example, THF (tetrahydrofuran) or chloroform can be used. The colorant can be extracted with an appropriate solvent and can be determined from the amount of extraction. Furthermore, if there is a specific element in the pigment structure used, such as copper element in copper phthalocyanine, use an absolute quantitative value by ICP-MS (high frequency inductively coupled plasma mass spectrometry) or a calibration curve. Thus, it can be easily obtained by fluorescent X-ray analysis. The total amount of colorant in the examples of the present invention was calculated from this because the prescription amount was known.

The amount of the colorant present near the surface of the toner can be easily measured by FTIR (Fourier transform infrared spectroscopy) -ATR method (total reflection method). A detailed procedure example is described below.
In advance, a known amount of a colorant such as a pigment and a toner material such as a binder resin are sufficiently uniformly and finely dispersed in an agate mortar or the like, and a pellet sample is prepared using a molding machine. The above measurement is performed on the surface of the pellet sample, and an IR spectrum in which the X axis is wave number (cm ⁻¹ ) and the Y axis is absorbance is obtained. In the obtained spectrum, the peak intensity of a characteristic peak derived from the structure of the binder resin and not overlapping with the peak derived from the structure of other raw materials in the sample is defined as Pr. Similarly, the peak intensity of a characteristic peak derived from the structure of a colorant such as a pigment and not overlapping with the peak derived from the structure of another raw material in the sample is defined as Pp. There is no problem even if the absorbance of the peak is used as the peak intensity, but the valleys between the peaks before and after the peak to be measured are connected by a tangent, the tangent is used as a base line, the peak top (A), and the X-axis perpendicular passing through A It is preferable that the distance (AB) between the intersection points (B) of the baseline is the peak intensity. Moreover, as long as the conditions are satisfied, the peak intensity of any peak may be used and is not particularly limited. In the present invention, the peak intensity of a peak found in the vicinity of 828 cm ⁻¹ derived from the out-of-plane skeletal vibration of the aromatic ring contained in the structure of the binder resin is Pr, and C of the aromatic ring contained in the structure of the colorant The peak intensity of the peak observed in the vicinity of 755 cm ⁻¹ that originates from the −H out-of-plane bending vibration is defined as Pp. The depth of analysis by the ATR method is wavelength-dependent, and in the present invention, the wavelength of the colorant-derived peak is 755 cm ⁻¹ , and is about 1.0 μm. From this, the peak intensity ratio (P) derived from the colorant in the vicinity of the surface can be obtained from P = Pp / Pr. By the above method, a calibration curve for the amount of colorant such as the peak intensity ratio (P) and the vicinity of the surface was prepared.
Next, the IR spectrum of the surface of the toner made into a pellet sample by a molding machine is measured, and the peak intensity ratio (P) derived from the colorant near the surface is obtained in the same manner as described above. it can be obtained colorant abundance ratio. In the present invention, a pellet sample was prepared by applying a load of 6 t to 3 g of toner for 1 minute using a molding machine, and the surface was measured using an FTIR microscope ATR apparatus Spectrum One (manufactured by Perkin Elmer).

In the present invention, the colorant abundance ratio of the toner particle surface of the yellow toner (Py) must be a 1.3 to 2.0, preferably 1.5 to 1.8, more preferably 1 .6 to 1.8. If the value is smaller than this value, the amount of colorant appropriate for the present invention is not in the vicinity of the surface, so that hot offset is likely to occur. If the value is larger than this value, the surface colorant, for example, a pigment inhibits the fixing property. Further, cold offset and smear resistance are deteriorated, and the colorant is excessively unevenly distributed, so that sufficient color reproducibility and color developability cannot be obtained. Furthermore, it is a problem because a proper charging characteristic cannot be obtained by a colorant such as a pigment on the surface.

  Any color toner other than the yellow toner can be used as long as the conditions are satisfied. However, it is common to use a magenta toner and a cyan toner from the viewpoint of color reproducibility of a full color image. preferable. The optimum ratio of the surface colorant abundance (Pm) of the magenta toner is 1.2 to 1.7, preferably 1.3 to 1.5. The ratio of the amount of the surface colorant (Pc) in the cyan toner is in an optimal range of 1.0 to 1.7, preferably 1.3 to 1.5. If it is smaller than these values, hot offset is likely to occur as in the case of yellow toner. On the other hand, if the value is larger than these values, the fixability, color reproducibility, color developability, and charging characteristics are deteriorated similarly to the yellow toner. Further, when the relationship of Pm <Py or Pc <Py is satisfied, the effect of the present invention can be further obtained, and the fixability, color reproducibility, and color developability can be drastically improved.

  In the present invention, in an overlapping state of Y (yellow), M (magenta), and C (cyan) that reproduce R (red), G (green), and B (blue), which are intermediate colors, at least one intermediate color, The toner having the highest surface colorant abundance ratio only needs to be an upper layer, but the toner having the highest surface colorant abundance ratio in two or more intermediate colors and the upper layer is the upper layer. It is desirable from the viewpoint of exhibiting.

  In addition, in the superimposed state of Y and C that reproduces the intermediate color R and the superimposed state of Y and M that reproduces the intermediate color G, it is sufficient that Y is an upper layer in at least one intermediate color. , It is preferable that both Y are in the upper layer in the overlap state of both R and G.

<Volume average particle diameter / number average particle diameter>
In the toner of the present invention, the volume average particle diameter (Dv) of the toner particles is preferably 3.0 to 7.0 μm, and more preferably 3.5 to 6.0 μm. Further, the ratio (Dv / Dn) to the number average particle diameter (Dn) is preferably 1.25 or less, more preferably 1.10 to 1.20, and particularly preferably 1.10. It is preferable to be within the range of 1.15. Here, the volume average particle diameter is defined as Dv = [(Σ (nD ³ ) / Σn) ^1/3 (where n is the number of particles and D is the particle diameter). By setting the volume average particle diameter (Dv) and the ratio (Dv / Dn) of the toner particles of the toner of the present invention within the above ranges, a high-quality image excellent in fine line reproducibility and granularity can be obtained. Can do. In general, it is said that the smaller the particle diameter of the toner, the more advantageous it is for obtaining a high-resolution and high-quality image. Conversely, if the toner particle size is larger than this value, it will be difficult to obtain a high-resolution and high-quality image, and the toner particle size will be reduced when the toner in the developer is balanced. In many cases, the fluctuation becomes large. It was also clarified that the same applies when the volume average particle diameter / number average particle diameter (Dv / Dn) is too large. Furthermore, when (Dv / Dn) is too small, there are some aspects that are preferable from the viewpoint of stabilizing the behavior of the toner and uniformizing the charge amount, but there are cases where the toner is insufficiently charged and cleaning is also performed. It became clear that it might worsen sex.
The volume average particle size (Dv) and the ratio of the volume average particle size (Dv) to the number average particle size (Dn) (Dv / Dn) are measured by COULTER TA-II (manufactured by COULTER ELECTRONICS, INC), etc. Is automatically measured. The aperture diameter is 100 μm.

<Circularity and circularity distribution>
The toner in the present invention preferably has a specific shape and shape distribution, and preferably has an average circularity of 0.940 to 0.990, and an average circularity of 0.960 to 0.985. More preferably, the degree is less than 0.94. The substantially spherical toner within the range of the average circularity is effective for forming a high-definition image having excellent transfer efficiency and reproducibility at an appropriate density. In addition, a good image with little transfer omission in a fine line image can be obtained. This is presumably because the toner surface is sufficiently smooth, the number of contact points with the image support is reduced, and the transfer failure of the toner to the transfer material is reduced. An irregularly shaped toner that is smaller than this range and too far away from the spherical shape tends to deteriorate the transferability, and conversely, if it is larger than this range and close to a sphere, the transferability is excellent. In a system that employs blade cleaning or the like, poor cleaning occurs on the photosensitive member and the transfer belt, causing stains on the image. For example, development or transfer with a low image area ratio results in a small amount of residual toner and poor cleaning is not a problem. However, when the image area ratio is high, such as a color photographic image, it is further The toner on which the transferred image is formed may be generated as a transfer residual toner on the photosensitive member, and if this is accumulated, the background stain of the image occurs. In addition, there is a problem that the charging roller or the like that contacts and charges the photosensitive member is contaminated, and the original charging ability is not exhibited.

  The average circularity can be measured using a flow type particle image analyzer FPIA-2100 (manufactured by Sysmex Corporation). The measurement was adjusted to a 1% NaCl aqueous solution using primary sodium chloride and then passed through a 0.45 μm filter to 50 to 100 ml of a surfactant, preferably 0.1 to 5 ml of an alkylbenzene sulfonate as a dispersant. In addition, add 1-10 mg of sample. This was subjected to a dispersion treatment for 1 minute with an ultrasonic disperser and measured using a dispersion liquid in which the particle concentration was adjusted to 5000 to 15000 particles / μl. The diameter of a circle having the same area as a two-dimensional image captured by a CCD camera is assumed to be the equivalent circle diameter, and the equivalent circle diameter of 0.6 μm or more is effective from the accuracy of CCD pixels, and is used for calculating the average circularity. It was. The average circularity can be obtained by calculating the circularity of each particle, adding the circularity of each particle, and dividing by the total number of particles. The average circularity of each particle can be calculated by dividing the circumference of a circle having the same projected area as the particle image by the circumference of the particle projection image.

<Toner for electrostatic image development>
The toner production method and materials used in the present invention are not particularly limited, and any known ones can be used as long as the conditions are satisfied. However, from the viewpoint of low-temperature fixability, the binder resin used is preferably a polyester resin. In the present invention, the toner contains a solution or dispersion of an organic solvent in which a polymer having a site capable of reacting at least with a compound having an active hydrogen group and an active hydrogen group, a release agent, and a colorant is dissolved or dispersed. The organic solvent and the like are removed and washed after being dispersed on a droplet in a medium and reacting or reacting the compound having the active hydrogen group and the polymer having a site capable of reacting with the active hydrogen group. The toner for developing an electrostatic image characterized by being dried was used. In the method for producing the polymerized toner, a polyester resin having high resin selectivity and high low-temperature fixability can be used. Moreover, it is excellent in granulation property and it is easy to control the particle size, particle size distribution, and shape. Furthermore, since the ratio of the amount of the surface colorant present can be easily controlled in the colorant dispersion step depending on the dispersion conditions, the toner produced by the above-described production method is preferable.

Below, the said manufacturing method and the material used are demonstrated.
[Organic solvent phase]
~ Organic solvent ~
The organic solvent used for forming the organic solvent phase in the present invention can be used without particular limitation as long as it can dissolve at least the functional group-containing polyester resin described later. In particular, since the organic solvent needs to be distilled off after the dispersion step of the organic solvent phase in the aqueous medium phase described later, the boiling point is less than 150 ° C. in order to facilitate the distillation step. It is preferable to use a volatile organic solvent.
Specific examples of the organic solvent used in the present invention include, for example, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, acetic acid. In addition to non-hydrophilic organic solvents such as methyl and ethyl acetate, methyl ethyl ketone, acetone, tetrahydrofuran and the like can be mentioned, and these can be used singly or in combination of two or more. Among these, non-halogen solvents are particularly preferable, and methyl acetate and ethyl acetate are preferable from the viewpoint of safety. The amount of solvent used relative to 100 parts of the toner composition is usually 40 to 300 parts, preferably 60 to 140 parts, and more preferably 80 to 120 parts.

~ Colorant ~
As the colorant used in the present invention, known dyes and pigments can be used. For example, naphthol yellow S, hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher as yellow colorants, Yellow lead, Titanium yellow, Polyazo yellow, Oil yellow, Hansa yellow (GR, A, RN, R), Pigment yellow L, Benzidine yellow (G, GR), Permanent yellow (NCG), Vulcan fast yellow (5G, R) ), Tartrazine lake, quinoline yellow lake, anthrazan yellow BGL, isoindolinone yellow, etc., carbon black, nigrosine dye, iron black, bengara, red lead, lead red, cadmium red, Cadmium Mercury Red, Antimon Zhu, Permanentre 4R, Parared, Faise Red, Parachlor Ortho Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Rake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Rune, Oil Red, Quinacridone Red, Pyrazolone Red, Polyazo Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-free Phthalocyanine Blue, Phthalocyanine blue, fast sky blue, indanthrene blue (RS, BC), indigo, ultramarine, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc Green, chromium oxide, pyridian, emerald green, pigment green B, naphthol green B, green go , Acid green lake, malachite green lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used.
Among these, regarding the yellow colorant, it is preferable to use an azo pigment or a quinacridone pigment because it is most excellent in maintaining the electric resistance of the toner surface appropriately.

  The amount of the colorant used is usually 1 to 15% by weight, preferably 3 to 10% by weight as the content in the toner of the present invention.

The colorant used in the present invention can also be used as a master batch combined with a resin.
As the binder resin (binder resin) kneaded together with the production of the master batch or the master batch, for example, in addition to the urea-modified polyester resin and the non-reactive polyester resin, polystyrene, poly p-chlorostyrene, polyvinyl toluene, etc. Styrene and its substituted polymers: styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer Styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-methacrylic acid Butyl copolymer, styrene α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinylmethylketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene -Styrene copolymers such as maleic acid copolymer, styrene-maleic acid ester copolymer; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol Resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. These may be used alone or in combination of two or more.

This master batch can be obtained by mixing and kneading a resin for a master batch and a colorant under a high shear force. At this time, an organic solvent can be used in order to enhance the interaction between the colorant and the resin. In addition, a so-called flushing method, which is a wet cake of a colorant, is a method of mixing and kneading an aqueous paste containing water of a colorant together with a resin and an organic solvent, transferring the colorant to the resin side, and removing moisture and organic solvent components. Since it can be used as it is, it does not need to be dried and is preferably used.
For mixing and kneading, a high shearing dispersion device such as a three-roll mill is preferably used.
The colorant or masterbatch can be dissolved or dispersed in the organic solvent phase, but is not limited thereto.

-Functional group-containing polyester resin-
In the present invention, a functional group-containing polyester resin can be preferably used as the polymer having a site capable of reacting with an active hydrogen group. The functional group-containing polyester resin used in the present invention is dissolved in the organic solvent and, as will be described later, undergoes an extension reaction and / or a crosslinking reaction with an active hydrogen-containing compound to be described later in an aqueous medium, resulting in a higher molecular weight toner. It is a component that forms a binder (binder resin).

Examples of the functional group-containing polyester resin include a polyester prepolymer having a functional group that reacts with active hydrogen such as an isocyanate group.
The polyester prepolymer preferably used in the present invention is the polyester prepolymer (A) having this isocyanate group. This polyester prepolymer (A) is produced by reacting a polyisocyanate (PIC) with a polyester having a polycondensate of a polyol (PO) and a polycarboxylic acid (PC) and having an active hydrogen group. Examples of the active hydrogen group possessed by the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Among these, an alcoholic hydroxyl group is preferable. Examples of the polyol include diol (DIO) and trivalent or higher polyol (TO), and DIO alone or a mixture of DIO and a small amount of TO is preferable. Diols include alkylene glycols (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, etc.) Alkylene ether glycol (diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diol (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenol (Bisphenol A, bisphenol F, bisphenol S, etc.); alkylene oxides of the alicyclic diols (ethylene oxide, propylene oxide, butylene) Kisaido etc.) adducts; alkylene oxide (ethylene oxide of the bisphenols, propylene oxide, butylene oxide, etc.) adducts.
Among these, alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols are preferable. Particularly preferred are alkylene oxide adducts of bisphenols and combinations thereof with alkylene glycols having 2 to 12 carbon atoms. Examples of the trihydric or higher polyol include 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (trisphenol PA, Phenol novolac, cresol novolac, etc.); alkylene oxide adducts of the above trivalent polyphenols and the like. Examples of the polycarboxylic acid (PC) include dicarboxylic acid (DIC) and trivalent or higher polycarboxylic acid (TC), and DIC alone or a combination of DIC and a small amount of TC is preferable. Dicarboxylic acids include alkylene dicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, etc.) ) And the like. Among these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher polycarboxylic acid include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). The polycarboxylic acid may be subjected to a condensation reaction with a polyol as the acid anhydride or lower alkyl ester (methyl ester, ethyl ester, isopropyl ester, etc.) described above.

  In order to prepare a polyester having an alcoholic hydroxyl group at the terminal by a polycondensation reaction, the polyol component and the polycarboxylic acid component are used in an equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. Usually, it is 2/1 to 1/1, preferably 1.5 / 1 to 1/1, and more preferably 1.3 / 1 to 1.02 / 1.

  Examples of the polyisocyanate (PIC) used to prepare the polyester prepolymer (A) by reacting with the alcoholic hydroxyl group of the polyester include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-di-). Isocyanatomethyl caproate); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α ′ -Tetramethylxylylene diisocyanate, etc.); isocyanurates; those obtained by blocking the polyisocyanate with phenol derivatives, oximes, caprolactam, etc .; and Combinations of two or more of these and the like.

  The use ratio of the polyisocyanate is usually 5/1 to 1/1, preferably 4/1, as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. To 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. If the equivalent ratio is too high, the low-temperature fixability of the obtained toner may be deteriorated. On the other hand, if the equivalent ratio is too low, the urea bond content in the reaction product with amines will be low, and the resulting toner will be resistant to hot offset. This is not preferable because the properties may deteriorate.

  The number of isocyanate groups contained per molecule in the polyester prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2 on average. Five. If it is less than 1 per molecule, the molecular weight of the urea-modified polyester will be low, and the hot offset resistance will deteriorate.

  In the present invention, as described above, the polyester prepolymer (A) is used by being dissolved in the organic solvent phase. The amount used and the amount of the polyester prepolymer (A) is 10 to 55% by weight as the content in the toner base. , Preferably 10 to 40% by weight, more preferably 15 to 30% by weight.

-Combination of non-reactive low molecular weight polyester-
In the present invention, as a toner binder (binder resin) component, not only the elongation reaction and / or crosslinking reaction product of the functional group-containing polyester resin and the active hydrogen compound described below, but also non-reactive polyester (PE) Can be used together by dissolving in an organic solvent phase. By using this PE in combination, the low-temperature fixability of the toner of the present invention and the glossiness when used in a full-color apparatus are improved, which is preferable to the case where the elongation reaction and / or crosslinking reaction product is used alone. Examples of PE include a polycondensate of a polyol and a polycarboxylic acid similar to the polyester used for the reaction with the polyisocyanate (PIC), and preferable ones are also the same as described above.

  Moreover, PE may be modified not only with unmodified polyester but also with a chemical bond other than a urea bond, for example, with a urethane bond. When formed into a toner, it is preferable in terms of low-temperature fixability and hot offset resistance that the elongation reaction and / or crosslinking reaction product and PE are at least partially compatible. Therefore, the polyester prepolymer (A) and PE preferably have similar compositions.

  In the present invention, when PE is contained in the organic solvent phase, the blending amount is 10/90 to 55/45, preferably 10/90 to 40 / as the weight ratio of the polyester prepolymer (A) and PE. 60, more preferably 15/85 to 30/70. When the weight ratio of the polyester prepolymer (A) is too low, hot offset resistance is deteriorated and it is difficult to achieve both heat-resistant storage stability and low-temperature fixability.

  In the present invention, the peak molecular weight of the weight average molecular weight measured by GPC (gel permeation chromatography) of PE is 5000 to 25000, preferably 8000 to 20000, and more preferably 13,000 to 18000. If the molecular weight is too low, the heat-resistant storage stability is deteriorated, whereas if it is too high, the low-temperature fixability is deteriorated.

  In the present invention, the acid value of PE is 15 to 45 mgKOH / g, preferably 20 to 35 mgKOH / g. Thus, by using a medium to high acid value PE resin, the low-temperature fixability can be improved without impairing the hot offset resistance. If the acid value is lower than this range, improvement in low-temperature fixability cannot be expected so much. On the other hand, if the acid value is too high, the reaction between the active hydrogen and the prepolymer tends to be inhibited, and the granulation property is lowered or the negative chargeability is reduced. It tends to be too strong and is not preferred.

Moreover, it is preferable that the hydroxyl value of PE is 5 or more, More preferably, it is 10-120, Most preferably, it is 20-80. If the hydroxyl value is too low, it is difficult to achieve both heat-resistant storage stability and low-temperature fixability.
The organic solvent phase is further blended with toner binder (binder resin) components other than those described above, for example, conventionally known toner binder components such as styrene resin, acrylic resin, epoxy resin, and styrene-acrylic acid ester copolymer. It can be done.

[Active hydrogen-containing compounds]
As will be described later, the above-mentioned polyester prepolymer (A) having an isocyanate group is made to have a higher molecular weight by an extension reaction and / or a crosslinking reaction with an active hydrogen compound.

  As the active hydrogen compound used in the present invention, amines (B) are preferably used, and a urea-modified polyester resin (UMPE) can be obtained by reaction with the isocyanate group of the polyester prepolymer (A). This has excellent performance as a toner binder (binder resin) component.

  Examples of the amines (B) include diamine (B1), trivalent or higher polyamine (B2), amino alcohol (B3), amino mercaptan (B4), amino acid (B5), and amino acids (B1) to (B5). What blocked the group (B6) etc. are mentioned. Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-dimethyldicyclohexylmethane, diamino). Cyclohexane, isophorone diamine, etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine, etc.) and the like. Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. As (B6) which blocked the amino group of (B1) to (B5), a ketimine compound obtained from the amines of the above (B1) to (B5) and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), And oxazolidine compounds. Among these amines (B), preferred are (B1) and a combination of (B1) and a small amount of (B2).

  Furthermore, if necessary, the molecular weight of a modified polyester such as a urea-modified polyester can be adjusted using an elongation terminator. Examples of the elongation terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).

  The use ratio of the amines (B) is equivalent to the isocyanate group [NCO] in the prepolymer (A) having an isocyanate group and the amino group [NHx] (x is 1 or 2) in the amines (B). The ratio [NCO] / [NHx] is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 1 / 1.2. . If the equivalent ratio is too high or too low, the molecular weight of the urea-modified polyester becomes low, and the hot offset resistance of the resulting toner deteriorates.

  In the present invention, the polyester modified with a urea bond may contain a urethane bond (—O (CO) NH—) together with a urea bond (—NH (CO) NH—). The molar ratio between the urea bond content and the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

-Properties of toner binder (binder resin)-
In the present invention, as described above, a urea-modified polyester resin obtained by reaction of the polyester prepolymer (A) and the amines (B) is used as a toner binder component, and a non-reactive polyester or the like is used. Other components (including a resin used in the preparation of the colorant master batch described later) are also used in combination.

  In the present invention, the glass transition point (Tg) of the toner binder is 50 to 70 ° C., preferably 55 to 65 ° C. If Tg is too low, the heat-resistant storage stability of the toner is deteriorated. Conversely, if Tg is too high, the low-temperature fixability becomes insufficient. In the dry toner of the present invention, the use of a urea-modified polyester resin or the like tends to have good heat-resistant storage stability even when the glass transition point is low as compared with known polyester toners. As the storage elastic modulus of the toner binder, the temperature (TG ′) at which the measurement frequency is 20 Hz becomes 1000 Pa is usually 100 ° C. or higher, preferably 110 to 200 ° C. When the TG ′ is too low, the hot offset resistance is deteriorated. As the viscosity of the toner binder, the temperature (Tη) at which the measurement frequency is 20 Hz becomes 100 Pa · s is usually 180 ° C. or less, preferably 90 to 160 ° C. If the Tη is too high, the low-temperature fixability deteriorates. That is, TG ′ is preferably higher than Tη from the viewpoint of achieving both low temperature fixability and hot offset resistance. In other words, the difference between TG ′ and Tη (TG′−Tη) is preferably 0 ° C. or more. More preferably, it is 10 degreeC or more, Most preferably, it is 20 degreeC or more. The upper limit of the difference is not particularly limited. Further, from the viewpoint of achieving both heat-resistant storage stability and low-temperature fixability, the difference between Tη and Tg is preferably 0 to 100 ° C. More preferably, it is 10-90 degreeC, Most preferably, it is 20-80 degreeC.

[Aqueous medium phase]
~ Aqueous medium ~
In the present invention, the aqueous medium in which the resin fine particles described later are dispersed to form the aqueous medium phase may be water alone, or a solvent miscible with water may be used in combination. Examples of miscible solvents include alcohols (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.), and the like. These can be used singly or in combination of two or more.

  Furthermore, in order to reduce the viscosity when the resin component contained in the organic solvent phase is dispersed in an aqueous medium, a solvent in which the polyester prepolymer (A) is soluble can be used in combination. The use of the solvent is preferable in that the particle size distribution of the toner particles becomes sharp. The solvent is preferably volatile with a boiling point of less than 100 ° C. because it can be easily distilled off. Examples of the solvent include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, Examples thereof include methyl ethyl ketone and methyl isobutyl ketone, and these can be used singly or in combination of two or more. Particularly preferred are aromatic solvents such as toluene and xylene; halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform and carbon tetrachloride; and methyl acetate and ethyl acetate. The usage-amount of the solvent with respect to 100 parts of prepolymers (A) is 0-300 parts normally, Preferably it is 0-100 parts, More preferably, it is 25-70 parts. When the solvent is used, after the urea-modified polyester is formed, it is distilled off by heating under normal pressure or reduced pressure like other organic solvents.

~ Resin fine particles ~
In the present invention, the aqueous medium phase in which resin fine particles are dispersed can be preferably used. In the present invention, the average particle size of the resin fine particles dispersed and used in the aqueous medium is 5 to 200 nm, preferably 20 to 300 nm. The resin fine particles are components that function as an external additive that binds to the surface or surface layer of the dispersed particles formed by dispersing the organic medium in the aqueous medium phase and coats the formed toner particles. .

  The resin fine particles preferably have a glass transition point (Tg) of 40 to 90 ° C, and more preferably in the range of 50 to 70 ° C. If the Tg is too low, toner storage stability is deteriorated, and blocking occurs during storage and in the developing machine. On the other hand, if it is too high, the resin fine particles (B) inhibit the adhesiveness to the fixing paper, and the minimum fixing temperature rises, so that a sufficient fixing temperature range cannot be secured. Inconveniences such as being unable to be removed or being peeled off when the fixed image is rubbed occur.

  The weight average molecular weight is preferably 200,000 or less, more preferably 50,000 or less. The lower limit is usually 4000. If the weight average molecular weight is too high, the resin fine particles inhibit the adhesion to the fixing paper, and the minimum fixing temperature is increased.

As the resin fine particles, known resins can be used as long as they can form a dispersion in an aqueous medium, and may be thermoplastic resins or thermosetting resins. For example, vinyl resins, polyurethane resins, epoxy resins, Examples thereof include polyester resin, polyamide resin, polyimide resin, silicon resin, phenol resin, melamine resin, urea resin, aniline resin, ionomer resin, and polycarbonate resin. These can be used singly or in combination of two or more. Among these, vinyl resins, polyurethane resins, epoxy resins, polyester resins, or combinations thereof are preferable because an aqueous dispersion of fine spherical resin particles is easily obtained. Vinyl resins are polymers obtained by homopolymerization or copolymerization of vinyl monomers, such as styrene- (meth) acrylic acid ester copolymers, styrene-butadiene copolymers, (meth) acrylic acid-acrylic acid ester copolymers. Examples thereof include a polymer, a styrene-acrylonitrile copolymer, a styrene-maleic anhydride copolymer, and a styrene- (meth) acrylic acid copolymer.
The dispersion / blending amount of the resin fine particles in the aqueous medium is preferably 0.5 to 10 wt% with respect to the organic solvent phase. If it is not within this range, emulsification failure occurs and granulation cannot be performed. More preferably, it is 1 to 3 wt%.

  As described above for a while, the resin fine particles are used for the purpose of controlling (aligning) the toner shape (circularity, particle size distribution, etc.), and are mainly unevenly distributed on the surface of the toner particles to be formed. The surface coverage by the resin fine particles with respect to the toner particles is preferably in the range of 1 to 90%, more preferably in the range of 5 to 80%. If the surface coverage is too high, the surface of the toner particles is almost completely covered with resin fine particles, and bleeding out of the release agent inside the toner particles to the toner particle surface is inhibited, and a releasing effect is obtained. As a result, the offset to the fixing roller occurs. Conversely, if the surface coverage is too low, the adhesion between the toner particles tends to work, and the toner tends to aggregate. Therefore, the fluidity of the toner is deteriorated, which is not preferable.

[Other ingredients]
~Release agent~
In the toner of the present invention, a release agent (wax) may be contained together with the binder resin and the colorant. Known waxes can be used, and examples thereof include polyolefin waxes (polyethylene wax, polypropylene wax, etc.); long chain hydrocarbons (paraffin wax, sazol wax, etc.); carbonyl group-containing waxes, and the like. Of these, carbonyl group-containing waxes are preferred. Examples of the carbonyl group-containing wax include polyhydric alcohol carboxylates (carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1 , 18-octadecanediol distearate, etc.); polyvalent carboxylic esters (tristearyl trimellitic acid, distearyl maleate, etc.); polyvalent amine carboxylic acid amides (ethylenediamine dibehenyl amide, etc.); polyvalent carboxylic acid amides (tri Meritic acid tristearyl amide, etc.); and dialkyl ketones (distearyl ketone, etc.). Among these carbonyl group-containing waxes, polyhydric alcohol carboxylic acid esters such as pentaerythritol tetrabehenate are preferable. The melting point of the wax used in the present invention is usually 40 to 160 ° C, preferably 50 to 100 ° C, and more preferably 50 to 70 ° C. A wax having a melting point that is too low adversely affects heat-resistant storage stability. Conversely, a wax having a melting point that is too high tends to cause a cold offset during fixing at a low temperature. The melt viscosity of the wax is preferably 5 to 1000 mPa · s, more preferably 10 to 100 mPa · s, as a measured value at a temperature 20 ° C. higher than the melting point. The wax having a too high melt viscosity has a poor effect of improving hot offset resistance and low-temperature fixability.

The amount of the wax used is usually 0 to 40% by weight, preferably 3 to 30% by weight as the content in the toner base of the present invention.
The wax can be dissolved or dispersed in the organic solvent phase, but is not limited thereto.

~ Charge control agent ~
The toner of the present invention may contain a charge control agent as necessary. Known charge control agents can be used. For example, nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified) Quaternary ammonium salts), alkylamides, phosphorus simple substances or compounds, tungsten simple substances or compounds, fluorine-based activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Nitronine-based dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, oxynaphthoic acid metal complex E-82, salicylic acid metal complex E- 84, E-89 of a phenol-based condensate (manufactured by Orient Chemical Industry Co., Ltd.), TP-302 of a quaternary ammonium salt molybdenum complex, TP-415 (manufactured by Hodogaya Chemical Industry Co., Ltd.), quaternary ammonium Copy charge PSY VP2038 of salt, copy blue PR of triphenylmethane derivative, copy charge NEG VP2036 of quaternary ammonium salt, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit), copper phthalocyanine, perylene, quinacridone, Zone-based pigment, a sulfonic acid group, a carboxyl group, and polymer compounds having a functional group such as a quaternary ammonium salt.

  In the present invention, the amount of charge control agent used is determined by the toner production method including the type of binder resin, the presence or absence of additives used as necessary, and the dispersion method, and is uniquely limited. However, it is preferably used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the main charge control agent is reduced, the electrostatic attractive force with the developing roller is increased, the flowability of the developer is reduced, and the image density is reduced. In addition to causing a decrease, it is difficult to obtain the effect of the present invention due to the colorant present in the vicinity of the toner surface. These charge control agents can be dissolved and dispersed after being melt-kneaded with a masterbatch or resin, and of course, they may be added when dissolved or dispersed directly in an organic solvent. It is preferable to make it.

[Preparation of toner particles]
The toner particles in the present invention can be prepared by the following method.
-Dispersion and reaction of organic solvent phase-
As described above, in the toner particles, the organic solvent phase containing the polyester prepolymer (A) is dispersed in the aqueous medium phase together with the amines (B), and an elongation reaction and / or a crosslinking reaction is performed in the aqueous medium phase. To form a urea-modified polyester.

  The colorant or colorant masterbatch, release agent and charge control agent together with the polyester prepolymer (A) and the non-reactive polyester may be dissolved or dispersed in advance in the organic solvent phase. Although most preferable for controlling the abundance ratio, a colorant or a colorant masterbatch, a release agent and a charge control agent may be mixed when dispersed in an organic solvent phase in an aqueous medium. In the present invention, the colorant or the colorant master batch and the charge control agent may be added and blended after the toner particles are formed. For example, the charge control agent is preferably driven after the toner particles are formed, and after the toner particles not containing the colorant are formed, the colorant can be added by a known dyeing method.

Surface colorant abundance ratio can be easily controlled by mixing and dispersing step of the non-reactive polyester is in the above-described colorant and a binder resin. In the present invention, a colorant masterbatch in which the colorant is sufficiently finely dispersed and a non-reactive polyester are mixed with a non-hydrophilic solvent such as ethyl acetate and a water-miscible solvent such as MEK (methyl ethyl ketone) (for example, Disperse with ethyl acetate: MEK = 4: 1). The dispersion method is not particularly limited, and for example, known methods such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. Dispersed uniformly, and, as the finely dispersed, surface colorant abundance ratio tends to decrease. If the dispersion is not well done, the pigment can move relatively freely in the binder resin, and the colorant is unevenly distributed by moving to the water phase side by oil-water distribution at the stage of the emulsification process. It is thought to do. On the contrary, it is considered that when the dispersion is sufficiently performed, the filler effect by the colorant works, the structural viscosity of the binder resin increases, and it becomes difficult to move to the aqueous phase side during emulsification. The selection of the solvent to be mixed is also important because the mobility of the colorant is greatly affected by the speed and amount of the solvent that moves in the binder resin to the aqueous phase side during emulsification.
In the fixing nip region L, the transfer material and the fixing film are adjusted to have the same speed.

  Mixing of the polyester prepolymer (A) and the amines (B) (especially blocked ketimine) in the organic solvent phase may be performed before dispersion in the aqueous medium. When a blocked ketimine or the like is used as the amine (B), the block is removed in the aqueous medium, and the elongation and / or crosslinking reaction with the polyester prepolymer (A) can be performed. Further, the amine (B) may be added after the organic solvent phase is dispersed in the aqueous medium. When the amines (B) are added after the dispersion of the organic solvent phase, the reaction starts from the dispersed particle interface, urea-modified polyester is preferentially generated from the surface of the toner particles to be prepared, and a concentration gradient may be provided inside the particles. it can.

Examples of a method for stably forming a dispersion of an organic solvent phase and an amine (B) in an aqueous medium include a method in which a shearing force is applied and dispersed.
The dispersion method is not particularly limited, and known methods such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. The particle size of the dispersion is preferably 2 to 20 μm, and for this purpose, it is preferable to use a high-speed shearing method. When a high-speed shearing disperser is used, the number of rotations is not particularly limited, but is usually 1000 to 30,000 rpm, preferably 5000 to 20,000 rpm. The dispersion time depends on the processing amount and is not particularly limited. However, in the case of a batch method, it is usually about 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C. It is preferable that the temperature during dispersion is high because the viscosity of the polyester prepolymer (A) and the like contained in the organic solvent dispersed phase can be lowered and the dispersion is easy.

  The usage-amount of the aqueous medium (except resin fine particles) with respect to 100 parts of solid content contained in an organic solvent phase is 50-2000 weight part normally, Preferably it is 100-1000 weight part. If the amount used is too small, the dispersed state of the organic solvent phase becomes non-uniform, and toner particles having a predetermined particle diameter cannot be obtained. On the other hand, if it is too much, it is not particularly effective, disadvantageous in terms of cost, and not economical. Moreover, a dispersing agent can also be used as needed. The use of a dispersant is preferable in that the particle size distribution becomes sharp and the dispersion is stable.

  When the dispersant is used, examples of the dispersant include anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, and phosphate esters; alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, Cationic surfactants of amine salt type such as imidazoline, and quaternary ammonium salt type such as alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride Nonionic surfactants such as fatty acid amide derivatives and polyhydric alcohol derivatives; amphoteric boundaries such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-dimethylammonium betaine Active agents.

  Further, by using a surfactant having a fluoroalkyl group, a dispersion effect can be exhibited with a very small amount of use. Preferred examples of the anionic surfactant having a fluoroalkyl group include a fluoroalkylcarboxylic acid having 2 to 10 carbon atoms and a metal salt thereof, disodium perfluorooctanesulfonylglutamate, 3- [ω-fluoroalkyl ( C6-C11) oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11- C20) Carboxylic acid and its metal salt, Perfluoroalkylcarboxylic acid (C7 to C13) and its metal salt, Perfluoroalkyl (C4 to C12) sulfonic acid and its metal salt, Perfluorooctanesulfonic acid diethanolamide, N-propyl -N- (2hydroxy Ciethyl) perfluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphoric acid Examples include esters. As a trade name, Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.); Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.); Unidyne DS-101 DS-102 (Daikin Kogyo Co., Ltd.); Megafac F-l10, F-120, F-113, F-191, F-812, F-833 (Dainippon Ink Co., Ltd.); Xtop EF-102 , 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products); and Fgentent F-100, F150 (manufactured by Neos). Further, as the cationic surfactant, aliphatic quaternary ammonium such as aliphatic primary amine, secondary amine or secondary amine acid having a fluoroalkyl group, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, etc. Salts, benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, and the like. Trade names include Surflon S-121 (Asahi Glass Co., Ltd.), Florard FC-135 (Sumitomo 3M Co., Ltd.); Unidyne DS-202 (Daikin Kogyo Co., Ltd.); Xetop EF-132 (manufactured by Tochem Products); Footage F-300 (manufactured by Neos) and the like. Further, calcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite and the like can also be used as inorganic compound-based dispersants that are hardly soluble in water. Further, the dispersed droplets may be stabilized using a polymer protective colloid. For example, acids such as acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride; (meth) acrylic monomer containing hydroxyl group Bodies such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-acrylate Chloro-2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N-methyl Roll acrylamide, N-methylol methacrylamide, etc .; Vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, etc .; Esters of compounds containing vinyl alcohol and carboxyl groups, such as, for example, Pinyl acetate, vinyl propionate, vinyl butyrate, etc .; acrylamide, methacrylamide, diacetone acrylamide or methylol compounds thereof; acid chlorides such as acrylic acid chloride, methacrylic acid chloride; pinylpyridine, vinyl pyrrolidone, vinyl imidazole, ethyleneimine Homopolymers or copolymers of vinyl monomers such as those having a nitrogen atom such as the above or a heterocyclic ring thereof can be used. Also, polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxy Polyoxyethylenes such as ethylene stearyl phenyl ester and polyoxyethylene nonylphenyl ester; celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can also be used. In addition, when using an acid or alkali soluble material such as calcium phosphate salt as the dispersion stabilizer, the calcium phosphate salt is removed from the fine particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and then washing with water. To do. In addition, it can be removed by an operation such as enzymatic degradation. When a dispersant is used, the dispersant can remain on the surface of the toner particles, but the elongation and / or crosslinking reaction between the polyester prepolymer (A) and the amines (B) is completed. Thereafter, removal by washing or the like is preferable from the viewpoint of the charging characteristics of the toner of the present invention.

~ Toner particle molding ~
In order to remove the organic solvent and the like from the obtained dispersion, a method of gradually elevating the temperature of the entire system and completely removing the organic solvent in the droplets can be employed. Alternatively, the dispersion liquid can be sprayed into a dry atmosphere to completely remove the water-insoluble organic solvent in the droplets to form toner particles, and the aqueous dispersant can be removed by evaporation together. As the dry atmosphere, a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, or the like, particularly various air streams heated to a temperature equal to or higher than the boiling point of the highest boiling solvent used is generally used. Sufficient target quality can be obtained by short-time treatment using a spray dryer, belt dryer, rotary kiln or the like.

~ Application of external additives ~
The toner particles (base material) obtained by the operations and processes as described above are further treated on the surface with an external additive to obtain the toner of the present invention with improved fluidity, developability, chargeability and the like. . As the external additive for assisting, inorganic fine particles can be preferably used. The primary particle diameter of the inorganic fine particles is preferably 5 nm to 2 μm, and particularly preferably 5 nm to 500 nm. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The proportion of the inorganic fine particles used is preferably 0.01 to 5% by weight, particularly 0.01 to 2.0% by weight, based on the toner particles.

  Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, Examples thereof include diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. These can be used singly or in combination of two or more.

  Other than inorganic fine particles, polymer fine particles such as polystyrene, methacrylic ester-based or acrylate-based copolymers obtained by soap-free emulsion polymerization suspension polymerization or dispersion polymerization, silicone resins, benzoguanamine resins, polyamides Polymer particles such as a polycondensation system such as a thermosetting resin can be used.

  The external additive used for improving fluidization and the like is subjected to surface treatment in advance to make it hydrophobic, thereby preventing deterioration of the toner flow characteristics, charging characteristics and the like even under high humidity. be able to. Examples of the surface treatment agent include silane coupling agents, silylating agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, and modified silicone oils. Etc. are preferably exemplified.

  Further, for the purpose of improving the cleaning property when removing the developer after transfer remaining on the photosensitive member and the primary transfer medium, toner particles (base material) are made of, for example, zinc stearate, calcium stearate, stearic acid, etc. Fatty acid metal salt; for example, it can be treated with polymer fine particles produced by soap-free emulsion polymerization such as polymethyl methacrylate fine particles and polystyrene fine particles. The polymer fine particles used preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

<Two-component developer>
When the toner of the present invention is used for a two-component developer, it may be used by mixing with a magnetic carrier, and the content ratio of the carrier and the toner in the developer is 1 to 10 weights of toner with respect to 100 parts by weight of the carrier. Part is preferable, and the range of 5 to 10 parts by weight is more preferable.

As the magnetic carrier, conventionally known ones such as iron powder, ferrite powder, magnetite powder, magnetic resin carrier having a particle diameter of about 20 to 200 μm can be used.
Examples of the coating material for the magnetic carrier include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin; urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins; polystyrene resins such as polystyrene resins and styrene acrylic copolymer resins; Halogenated olefin resins such as vinyl chloride; polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin: polycarbonate resin, polyethylene resin, polyvinyl fluoride resin, polyvinylidene fluoride resin, polytrifluoroethylene resin, polyhexa Fluoropropylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride Fluoro such as terpolymers of emission and non-fluoride monomers including, and silicone resins.

Moreover, you may make conductive powder etc. contain in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide or the like can be used. These conductive powders preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance.
The toner of the present invention can also be used as a one-component magnetic toner that does not use a carrier, or a non-magnetic toner.

<Image forming apparatus>
Hereinafter, an image forming apparatus using the electrophotographic toner of the present invention or a two-component developer composed of the toner and a carrier will be described.
Note that the image forming apparatus of the present invention is not limited to the one described below, and any image forming apparatus can be used as long as the conditions shown in the claims are satisfied.

-Tandem type color image forming device-
An embodiment of a tandem color image forming apparatus of the present invention will be described. In the tandem type electrophotographic apparatus, as shown in FIG. 1, images on the respective photoreceptors (1) are sequentially transferred onto the sheet (s) conveyed by the sheet conveying belt (3) by the transfer means (2). As shown in FIG. 2, the image on each photoconductor 1 is once transferred to the intermediate transfer body (4) by the primary transfer means (2) and then transferred onto the intermediate transfer body 4 as shown in FIG. There is an indirect transfer system in which the image is transferred onto the sheet (s) by the secondary transfer means (5). The transfer means (5) is a transfer conveyance belt, but there is also a roller shape.

  Comparing the direct transfer type and the indirect transfer type, the former is a photoconductor (the sheet feeding device (6) on the upstream side of the tandem type image forming apparatus (T) in which 1 are arranged) and the downstream side. The fixing means (7) must be arranged, and there is a disadvantage that the fixing means (7) increases in size in the sheet conveying direction, whereas the latter can set the secondary transfer position relatively freely. ) And the fixing means (7) can be arranged so as to overlap the tandem type image forming apparatus (T), and there is an advantage that downsizing is possible.

  In the former, in order not to increase the size in the sheet conveying direction, the fixing unit (7) is disposed close to the tandem type image forming apparatus (T). Therefore, the fixing means (7) cannot be disposed with a sufficient margin that the sheet (s) can bend, and the impact (particularly thick sheet) when the leading edge of the sheet (s) enters the fixing means (7). And the fixing means (7) affects upstream image formation due to the difference in speed between the sheet conveying speed when passing through the fixing means (7) and the sheet conveying speed by the transfer conveying belt. There are easy drawbacks. On the other hand, in the latter case, the fixing unit (7) can be disposed with a sufficient margin that the sheet (s) can be bent, so that the fixing device 7 can hardly affect the image formation. .

In view of the above, recently, an indirect transfer type of tandem type electrophotographic apparatus has attracted attention.
In this type of color electrophotographic apparatus, as shown in FIG. 2, the transfer residual toner remaining on the photosensitive member (1) after the primary transfer is removed by the photosensitive member cleaning means (8) to remove the photosensitive member (8). 1) The surface was cleaned and prepared for another image formation. Further, the transfer residual toner remaining on the intermediate transfer member (4) after the secondary transfer is removed by the intermediate transfer member cleaning means (9) to clean the surface of the intermediate transfer member (4), and in preparation for the image formation again. It was.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 3 shows an embodiment of the present invention, which is a tandem indirect transfer type electrophotographic apparatus. In the figure, reference numeral (101) is a copying apparatus main body, (200) is a paper feed table on which it is placed, (300) is a scanner mounted on the copying apparatus main body (101), and (400) is an automatic document feeder mounted thereon. (ADF). The copying machine main body (101) is provided with an endless belt-shaped intermediate transfer member (10) in the center.
Then, as shown in FIG. 3, in the illustrated example, it is wound around three support rollers (14), (15) and (16) so as to be able to rotate and convey clockwise in the figure.
In this illustrated example, an intermediate transfer body cleaning means (17) for removing residual toner remaining on the intermediate transfer body (10) after image transfer is provided on the left of the second support roller (15) among the three.
Further, among the three, on the intermediate transfer member (10) stretched between the first support roller (14) and the second support roller (15), yellow, cyan and magenta are arranged along the transport direction. , Black image forming means (18) are arranged side by side to constitute a tandem image forming apparatus (20).
On the tandem image forming apparatus (20), an exposure means (21) is further provided as shown in FIG. On the other hand, a secondary transfer unit (22) is provided on the side opposite to the tandem image forming apparatus (20) with the intermediate transfer member (10) interposed therebetween. In the example shown in the figure, the secondary transfer means (22) is constituted by a secondary transfer belt (24), which is an endless belt, spanned between two rollers (23) and (23), and an intermediate transfer member (10) is provided. Through the third support roller (16), and the image on the intermediate transfer member (10) is transferred to the sheet.
Next to the secondary transfer means (22), a fixing means (25) for fixing the transferred image on the sheet is provided. The fixing means (25) is configured by pressing the pressure roller (27) against the fixing belt (26) which is an endless belt.
The secondary transfer means (22) described above is also provided with a sheet transport function for transporting the image-transferred sheet to the fixing means (25). Of course, as the secondary transfer means (22), a transfer roller or a non-contact charger may be disposed. In such a case, it is difficult to provide this sheet conveying function together.
In the illustrated example, a sheet is placed under such secondary transfer means (22) and fixing means (25) in order to record images on both sides of the sheet in parallel with the tandem image forming apparatus (20). A sheet reversing means (28) for reversing is provided.

Now, when making a copy using this color electrophotographic apparatus, the document is set on the document table (30) of the automatic document feeder (400). Alternatively, the automatic document feeder (400) is opened, a document is set on the contact glass 32 of the scanner (300), and the automatic document feeder (400) is closed and pressed by it.
When a start switch (not shown) is pressed, when the document is set on the automatic document feeder (400), the document is transported and moved onto the contact glass (32), and then the other contact glass (32). When a document is set on the scanner, the scanner (300) is immediately driven to travel on the first traveling body (33) and the second traveling body (34). Then, the first traveling body (33) emits light from the light source and further reflects the reflected light from the document surface toward the second traveling body (34) and is reflected by the mirror of the second traveling body (34). Then, the image is placed in the reading sensor (36) through the imaging lens (35) and the content of the original is read.
When a start switch (not shown) is pressed, one of the support rollers (14), (15), and (16) is driven to rotate by the drive motor (not shown), and the other two support rollers are driven to rotate. The transfer body (10) is rotated and conveyed. At the same time, the individual image forming means (18) rotates the photoconductor (140) to form black, yellow, magenta, and cyan monochrome images on each photoconductor (140). Then, along with the conveyance of the intermediate transfer member (10), these monochrome images are sequentially transferred to form a composite color image on the intermediate transfer member (10).

On the other hand, when a start switch (not shown) is pressed, one of the paper feed rollers (42) of the paper feed table (200) is selectively rotated, and one of paper feed cassettes (44) provided in multiple stages in the paper bank (43). The sheet is fed out from the sheet, separated one by one by a separation roller (45), put into a sheet feeding path (46), and conveyed by a conveying roller (47) to a sheet feeding path (48) in the copying machine main body (101). Guide and stop against the registration roller (49).
Alternatively, the sheet feeding roller (50) is rotated to feed out the sheets on the manual feed tray (51), separated one by one by the separation roller (52), and placed in the manual sheet feeding path (53). ) And stop.
Then, the registration roller (49) is rotated in synchronization with the composite color image on the intermediate transfer member (10), and the sheet is fed between the intermediate transfer member (10) and the secondary transfer means (22). A color image is recorded on the sheet after being transferred by the next transfer means (22).
The sheet after the image transfer is conveyed by the secondary transfer means (22) and sent to the fixing means (25). The fixing means (25) applies heat and pressure to fix the transferred image, and then the switching claw. It is switched at (55), discharged by the discharge roller (56), and stacked on the discharge tray (57). Alternatively, it is switched by the switching claw (55) and put into the sheet reversing means (28), where it is reversed and led again to the transfer position, and an image is recorded also on the back surface, and then the discharge tray (56) 57) Drain up.

On the other hand, the intermediate transfer body (10) after the image transfer is removed by the intermediate transfer body cleaning means (17) to remove residual toner remaining on the intermediate transfer body (10) after the image transfer, and the tandem image forming apparatus (20). To prepare for image formation again.
Here, the registration roller (49) is generally used while being grounded, but it is also possible to apply a bias for removing paper dust from the sheet.

  In the tandem image forming apparatus (20) described above, the individual image forming means (18) is more specifically, for example, as shown in FIG. 4, around the drum-shaped photoconductor (140), charging means (160), A developing means (61), a primary transfer means (62), a photosensitive member cleaning means (63), a charge eliminating means (64) and the like are provided. The reference numerals shown in FIG. 4 will be described. (65) is a developer on the developing sleeve, (68) is a stirring paddle, (69) is a partition plate, (71) is a toner concentration sensor, (72) is a developing sleeve, ( 73 is a doctor, 75 is a cleaning blade, 76 is a cleaning brush, 77 is a cleaning roller, 78 is a cleaning blade, 79 is a toner discharge auger, and 80 is a driving device.

-Fixing means (surf fixing device)-
As the fixing means in the present invention, a so-called surf fixing device that rotates and fixes a fixing film as shown in FIG. 5 was used. In detail, the fixing film is an endless belt-like heat-resistant film, and is fixed and supported by a driving roller, a driven roller, and a heater support provided below the rollers, which are support rotating members of the film. The heating body is arranged in a suspended manner.

The driven roller also serves as a tension roller for the fixing film, and the fixing film is rotationally driven in the clockwise direction by the rotational driving of the driving roller in the clockwise direction in the drawing. This rotational driving speed is adjusted to a speed at which the transfer material and the fixing film are equal in the fixing nip region L where the pressure roller and the fixing film are in contact with each other.
Here, the pressure roller is a roller having a rubber elastic layer having good releasability, such as silicon rubber, and a contact pressure of 4 to 10 kg of total pressure against the fixing nip region L while rotating counterclockwise. With pressure contact.

  The fixing film preferably has excellent heat resistance, releasability and durability, and a thin film having a total thickness of 100 μm or less, preferably 40 μm or less is used. For example, at least an image of a single layer film of a heat-resistant resin such as polyimide, polyetherimide, PES (polyether sulfide), PFA (tetrafluoroethylene bar fluoroalkyl vinyl ether copolymer resin), or a composite layer film, for example, a 20 μm thick film The contact surface is coated with a release coating layer of PTFE (tetrafluoroethylene resin), PFA or other fluororesin added with a conductive material to a thickness of 10 μm, or an elastic layer such as fluororubber or silicon rubber. It is a thing.

In FIG. 5, the heating body of the present embodiment is composed of a flat substrate and a fixing heater, and the flat substrate is made of a material having high thermal conductivity and high electrical resistivity, such as alumina, and is a surface in contact with the fixing film. Has a fixing heater formed of a resistance heating element in the longitudinal direction. Such a fixing heater is formed by coating an electric resistance material such as Ag / Pd or Ta ₂ N in a linear or belt shape by screen printing or the like. In addition, electrodes (not shown) are formed at both ends of the fixing heater, and the resistance heating element generates heat when energized between the electrodes. Furthermore, a fixing temperature sensor constituted by a thermistor is provided on the surface of the substrate opposite to the surface provided with the fixing heater.

The temperature information of the substrate detected by the fixing temperature sensor is sent to a control unit (not shown), and the amount of electric power supplied to the fixing heater is controlled by the control unit, and the heating body is controlled to a predetermined temperature.
The fixing means used in the present invention is of course not limited to the surf fixing apparatus as described above, but image formation using a fixing means that is excellent in color reproducibility and color development, is efficient, and can shorten the rise time. Since a device can be obtained, it is preferable to use a surf fixing device.

-Fixing means (electromagnetic induction heating method (IH fixing device))-
As shown in FIG. 6A, the fixing means in the present invention generates Joule heat by an eddy current generated in a magnetic metal member by an alternating magnetic field as shown in FIG. A so-called electromagnetic induction heating type fixing device (IH fixing device) is used.

  The fixing unit shown in FIG. 6A includes a heating roller (81) heated by electromagnetic induction of the induction heating unit (86), a fixing roller (82) arranged in parallel with the heating roller (81), and a heating unit. An endless belt-like heat-resistant belt that is stretched between a roller (81) and a fixing roller (82), is heated by a heating roller (81), and rotates in the direction of arrow A by at least the rotation of any of these rollers. Toner heating medium) (83), and a pressure roller (84) that is pressed against the fixing roller (82) via the belt (83) and rotates in the forward direction with respect to the belt (83). . The heating roller (81) is made of a hollow cylindrical magnetic metal member such as iron, cobalt, nickel, or an alloy of these metals, and has a low heat capacity and a high temperature rise. The fixing roller (82) includes, for example, a metal core (82a) made of stainless steel or the like, and an elastic member (82b) covered with a core metal (82a) in a solid or foamed heat-resistant silicone rubber. Consists of. In order to form a contact portion having a predetermined width between the pressure roller (84) and the fixing roller (82) by the pressing force from the pressure roller (84), the outer diameter is larger than that of the heating roller (81). is doing. With this configuration, the heat capacity of the heating roller (81) becomes smaller than the heat capacity of the fixing roller (82), and the heating roller (81) is rapidly heated to shorten the warm-up time. The belt 83 stretched between the heating roller (81) and the fixing roller (82) is heated at the contact portion (W1) with the heating roller 81 heated by the induction heating means 86. Then, the inner surface of the belt (83) is continuously heated by the rotation of the rollers (81) and (82). As a result, the entire belt is heated. The pressure roller (84) includes a cored bar (84a) made of a cylindrical member made of a metal having high thermal conductivity such as copper or aluminum, and heat resistance and toner separation provided on the surface of the cored bar (84a). It is comprised from the highly elastic elastic member (84b). In addition to the above metal, SUS may be used for the core metal (84a). The pressure roller (84) presses the fixing roller (82) via the belt (83) to form the fixing nip portion N. In this embodiment, the hardness of the pressure roller (84) is fixed. By making it harder than the roller (82), the pressure roller (84) bites into the fixing roller (82) (and the belt 83), and by this biting, the recording material (91) becomes the pressure roller (84). The recording material (91) has an effect of being easily separated from the surface of the belt (83) because it follows the circumferential shape of the surface.

  The induction heating means (86) for heating the heating roller (81) by electromagnetic induction includes, as shown in FIGS. 6 (a) and 6 (b) A and B, an excitation coil (87) which is a magnetic field generating means, And a coil guide plate (88) around which the exciting coil (87) is wound. The coil guide plate (88) has a semi-cylindrical shape disposed close to the outer peripheral surface of the heating roller (81). As shown in FIG. 6B, the excitation coil 87 is a single long excitation coil wire. Are wound alternately along the coil guide plate 88 in the axial direction of the heating roller (81). The exciting coil (87) is connected to a driving power source (not shown) whose frequency is variable. On the outside of the excitation coil (87), a semi-cylindrical excitation coil core (89) made of a ferromagnetic material such as ferrite is fixed to the excitation coil core support member (90) and is arranged close to the excitation coil (87). Yes. In the present embodiment, the exciting coil core (89) having a relative permeability of 2500 is used. The excitation coil (87) is fed with a high frequency alternating current of 10 kHz to 1 MHz, preferably a high frequency alternating current of 20 kHz to 800 kHz from the drive power supply, thereby generating an alternating magnetic field. The alternating magnetic field acts on the heat generating layer of the heating roller (81) and the belt (83) in the contact area (W1) between the heating roller (81) and the heat-resistant belt (83) and in the vicinity thereof. Then, the eddy current I flows in the direction B that prevents the change of the alternating magnetic field. This eddy current I generates Joule heat according to the resistance of the heat generating layer of the heating roller (81) and the belt (83), and heats mainly in the contact area between the heating roller (81) and the belt (83) and its vicinity. The roller (81) and the belt (83) having the heat generating layer are heated by electromagnetic induction.

The belt (83) heated in this way is sent from a thermosensitive element such as a thermistor arranged in contact with the inner surface of the belt (83) in the vicinity of the entrance side of the fixing nip (N). The belt inner surface temperature is detected by the temperature detecting means (85).
Of course, the fixing means used in the present invention is not limited to the above-described IH fixing apparatus, but a high-quality image having particularly excellent color reproducibility and color developability can be obtained, and a heat roller system can be used. It is preferable to use an IH fixing device because the heat transfer efficiency is higher than that of the fixing device, the warm-up time can be shortened, and an image forming apparatus using a fixing device capable of quick start and energy saving can be obtained.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples and comparative examples, but the present invention is not limited only to these examples. In the following examples, “parts” and “%” are based on weight unless otherwise specified.

<Creation of two-component developer>
When evaluating the image quality and the like of a copied image in this example and the comparative example, the performance of the toner of the present invention as a two-component developer was evaluated.
As a carrier used for the two-component developer, a ferrite carrier having an average particle diameter of 35 μm coated with a silicone resin with an average thickness of 0.5 μm is used, and 7 parts by weight of the toner is contained in 100 parts by weight of the carrier. A developer was prepared by uniformly mixing and charging using a tumbler mixer of the type that is rolled and stirred.
The carrier was prepared as follows. As a core material, 5000 parts of Mn ferrite particles (weight average diameter: 35 μm), and as a coating material, 450 parts of toluene, 450 parts of silicone resin SR2400 (made by Toray Dow Corning Silicone, nonvolatile content 50%), aminosilane SH6020 ( Using a coating liquid prepared by dispersing 10 parts of Toray Dow Corning Silicone) and 10 parts of carbon black with a stirrer for 10 minutes, the core material, the coating liquid, and a rotating bottom plate disk in the fluidized bed The coating liquid was applied to the core material by applying the coating liquid while forming a swirling flow provided with stirring blades. The obtained coated material was baked in an electric furnace at 250 ° C. for 2 hours to obtain the carrier.

<Image quality evaluation machine for copied images>
In the toners obtained in the following examples and comparative examples, four color developing sections sequentially develop each color on four photoconductors corresponding to the respective colors, and black toner, cyan toner, magenta toner on the recording medium The evaluation machine A is a full-color laser printer (modified by Ricoh's IPSiO Color 8100) adjusted by providing an oilless surf fixing device. The evaluation machine B is the same as the evaluation machine A except that the black toner, the yellow toner, the magenta toner, and the cyan toner are sequentially transferred onto the recording medium in this order. The (fixing device) was evaluated by an evaluation machine C which was improved to an oilless IH fixing device.

<Evaluation items>
The following items were evaluated for the performance of the toners obtained in the examples and comparative examples.
(1) Image granularity / sharpness Using the evaluation machines A, B, and C, 10,000 full-color photographic images were output in full color mode, and the degree of granularity and sharpness was visually evaluated. It is evaluated in five stages of ranks 1 to 5, rank 5 is the best, and rank 1 is the worst. In Table 2, the degree is 5 in the case of offset printing, 4 if slightly better than the conventional electrophotographic image, 3 in the case of the conventional electrophotographic image, and more than the conventional electrophotographic image. When it was slightly worse, it was displayed as 2, and when it was considerably worse than the conventional electrophotographic image, it was displayed as 1.
(2) Fine line reproducibility Using valuation machines A, B, and C, after running 30,000 full color image charts with 50% image area in full color mode, a 600 dpi full color thin line image is printed on Ricoh type 6000 paper. The degree of bleeding of the thin line was compared with that of the step sample. Evaluation is made in five stages of ranks 1 to 5, rank 5 is the best in fine line reproducibility, and rank 1 is the worst. In Table 2, the degree is 5 in the case of offset printing, 4 if slightly better than the conventional electrophotographic image, 3 in the case of the conventional electrophotographic image, and more than the conventional electrophotographic image. When it was slightly worse, it was displayed as 2, and when it was considerably worse than the conventional electrophotographic image, it was displayed as 1.
(3) Hot offset resistance / low temperature fixability Using evaluation machines A, B, and C, two-color superimposed solid images (30 mm × 80 mm) of red (R), green (G), and blue (B) Plain paper and cardboard transfer paper (Ricoh type 6200 and NBS Ricoh copy printing) with a toner adhesion of 0.80 ± 0.1 mg / cm ² (0.40 ± 0.05 mg / cm ² per toner color) Paper <135>), and the fixing performance was evaluated. A fixing test was performed by changing the temperature of the fixing belt, and an upper limit temperature at which hot offset did not occur on plain paper was defined as an upper limit fixing temperature. Table 2 shows the results in a rank of 1 to 5, and 5 when the fixing upper limit temperature is 220 ° C. or higher, 4 when 200 to 219 ° C., 3 when 185 to 199 ° C., and 170 to 184. In the case of ° C., it was 2. In the case of 169 ° C. or lower, it was 1.
Further, the minimum fixing temperature was measured with a thick paper. The lower limit fixing temperature was obtained by drawing the obtained fixed image with a load of 50 g using a drawing tester, and setting the fixing roller temperature at which the image was hardly scraped as the lower limit fixing temperature. Table 2 shows the results in a rank of 1 to 5, 5 when the fixing lower limit temperature is 130 ° C. or lower, 4 when 131 to 140 ° C., 3 when 141 to 150 ° C., and 151 to 160. In the case of ° C., it was 2. In the case of 161 ° C. or higher, it was 1.
(4) Haze Degree Using the evaluation machines A, B, and C, red (R), green (G), and blue (B) two-color superimposed solid images (30 mm × 80 mm) are each 0.80 ± 0. With a toner adhesion amount of 1 mg / cm ² (0.40 ± 0.05 mg / cm ² per toner color), the toner is output to a Ricoh OHP sheet type PPC-DX (fixing temperature 160 ± 2 ° C.). The haze degree was measured by a direct reading haze degree computer HGM-2DP type (manufactured by Suga Test Instruments Co., Ltd.). The haze degree is also referred to as haze, and is measured as a scale indicating the transparency of the toner. The lower the value, the higher the transparency, and the better the color developability when an OHP sheet is used. In Table 2, the results are represented by ranks of 1 to 5, and 5 when the haze is 20% or less, 4 when 21 to 30%, 3 when 31 to 50%, and 51 to 70%. In the case of 1, it was 2, and in the case of 71% or more, it was 1.

Example 1
~ Preparation of aqueous phase ~
990 parts of water, 80 parts of an aqueous dispersion of a vinyl resin (styrene salt copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate), 48.5% of sodium dodecyl diphenyl ether disulfonate 45 parts of an aqueous solution (Eleminol MON-7, manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate were mixed and stirred to obtain a milky white liquid. This is referred to as [aqueous phase].
~ Synthesis of ketimine ~
170 parts of isophorone diamine and 75 parts of methyl ethyl ketone were charged into a reaction vessel equipped with a stir bar and a thermometer, and reacted at 50 ° C. for 5 hours to obtain a blocked amine. This is referred to as [ketimine compound]. The amine value of this [ketimine compound] was 418.
~ Preparation of masterbatch ~
1200 parts of water, 50 parts of carbon black (Cabot Corporation, Regal 400R), 50 parts of polyester resin (manufactured by Sanyo Kasei, RS801), and further 30 parts of water are added and mixed with a Henschel mixer (manufactured by Mitsui Mining). The mixture was kneaded at 150 ° C. for 30 minutes using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain a carbon black masterbatch. This is designated as [Bk master batch]. In addition, C.I. I. PigmentRed 269, C.I. I. Pigment Blue 15: 2, C.I. I. A magenta master batch [M master batch], a cyan master batch [C master batch], and a yellow master batch [Y master batch] were prepared in the same manner except that Pigment Yellow 155 was used instead of carbon black.
~ Preparation of oil phase ~
A container equipped with a stir bar and a thermometer was charged with 500 parts of a polyester resin (manufactured by Sanyo Chemical Co., Ltd., RS801), 30 parts of carnauba wax, and 850 parts of ethyl acetate. After maintaining the time, it was cooled to 30 ° C. over 1 hour, and using a bead mill (Ultra Visco Mill, manufactured by IMEX), liquid feeding speed: 1 Kg / hr, disk peripheral speed: 6 m / second, 0.5 mm The wax was dispersed under the conditions of zirconia bead filling amount: 80% by volume and pass number: 3 times. Next, 110 parts of [Bk masterbatch] and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain a dissolved product. This is designated as [Bk raw material solution]. [M raw material solution], [C raw material solution], respectively, except that [M master batch], [C master batch], and [Y master batch] were used instead of [Bk master batch]. [Y raw material solution] was obtained.
[Bk raw material solution] 900 parts are transferred to a container, 50 parts of ethyl acetate and 165 parts of MEK are added, and using the above bead mill, liquid feeding speed: 1 Kg / hr, disk peripheral speed: 8 m / second, 0.5 mm A dispersion was obtained under the conditions of zirconia bead filling amount: 80% by volume and pass number: 3 times. This is designated as [Bk pigment / wax dispersion]. Also, instead of [Bk raw material solution], [M raw material solution] was used, and the bead mill dispersion conditions were as follows: liquid feed rate: 0.5 kg / hr, disk peripheral speed: 12 m / sec, 0.5 mm zirconia bead filling amount : A dispersion prepared by changing the conditions to 80% by volume and the number of passes: 3 times is referred to as [M pigment / wax dispersion]. Also, instead of [Bk raw material solution], [C raw material solution] was used, and the bead mill dispersion conditions were as follows: liquid feed rate: 0.5 kg / hr, disk peripheral speed: 10 m / sec, 0.5 mm zirconia bead filling amount : A dispersion prepared by changing the conditions to 80% by volume and the number of passes: 5 times is referred to as [C pigment / wax dispersion]. Also, instead of [Bk raw material solution], [Y raw material solution] was used, and the bead mill dispersion conditions were as follows: liquid feeding speed: 0.5 kg / hr, disk peripheral speed: 10 m / sec, 0.5 mm zirconia bead filling amount : A dispersion prepared by changing the conditions to 80% by volume and the number of passes: 3 times is referred to as [Y pigment / wax dispersion].
~ Emulsification ~
[Bk pigment / wax dispersion] 1772 parts, 50% ethyl acetate solution of prepolymer (number average molecular weight 3800, weight average molecular weight 15000, Tg 60 ° C., acid value 0.5, hydroxyl value 51, and free isocyanate content are 1.53 wt%) 100 parts and 7.5 parts of [ketimine compound] are put in a container, mixed for 1 minute at 5,000 rpm using a TK homomixer (manufactured by Tokushu Kika), 1200 parts were added and mixed with a TK homomixer at a rotational speed of 7,500 rpm for 20 minutes to obtain an aqueous medium dispersion. This is designated as [Bk emulsified slurry]. Further, instead of [Bk pigment / wax dispersion], [M pigment / wax dispersion], [C pigment / wax dispersion], and [Y pigment / wax dispersion] were used in the same manner. [M emulsified slurry], [C emulsified slurry], and [Y emulsified slurry] were obtained.
-Deorganic solvent, washing, drying-
[Bk emulsified slurry] is put into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, aging is performed at 45 ° C. for 4 hours to obtain a dispersion from which the organic solvent is distilled off. It was. After 100 parts of this dispersion was filtered under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (rotation speed: 12000 rpm for 10 minutes), and then filtered.
(2): 100 parts of a 10% aqueous sodium hydroxide solution was added to the filter cake of (1), mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
(3): 100 parts of 10% hydrochloric acid was added to the filter cake of (2), mixed with a TK homomixer (rotation speed: 12000 rpm for 10 minutes), and then filtered.
(4): 300 parts of ion-exchanged water was added to the filter cake of (3), mixed with a TK homomixer (rotation speed 12000 rpm for 10 minutes), and then filtered twice to obtain a filter cake.
This filter cake was dried at 45 ° C. for 48 hours in a circulating dryer, and sieved with a mesh having a mesh size of 75 μm to obtain toner base particles. This is referred to as [Bk toner base]. [M toner base], [C toner base], [C emulsion base], [C emulsion base], [C emulsion base], [C emulsion base] [Y toner base material] was obtained.

~ Mixing of external additives ~
100 parts by weight of the [Bk toner base material] obtained above, 1.0 part by weight of hydrophobic silica (manufactured by Clariant Japan) as an external additive, and 0.5 part by weight of hydrophobic titanium oxide (manufactured by Teica) were added to Henschel. The toner was obtained by mixing with a mixer and passing through a sieve having an aperture of 38 μm to remove aggregates. This is black toner [Bk toner 1]. In the same manner, except that [M toner base], [C toner base], and [Y toner base] are used instead of [Bk toner base], magenta toner [M toner 1] and cyan toner [C Toner 1] and yellow toner [Y toner 1] were obtained.
The resulting 4-color surface colorant abundance ratio of toner, the volume average particle diameter (Dv), Dv / Dn, the average circularity was as shown in Table 1.

Next, using the toner, a developer was prepared by the method described in <Preparation of two-component developer>, and Table 2 shows each evaluation result for the above <evaluation item>. Evaluation machine A was used as the evaluation machine.

Comparative Example 1
[Y Toner 2] was obtained in the same manner as in Example 1 except that the bead mill dispersion conditions of [Y pigment / wax dispersion] in the oil phase adjustment described in Example 1 were changed as follows. It was.
The resulting surface colorant abundance ratio of the toner, the volume average particle diameter (Dv), Dv / Dn, the average circularity was as shown in Table 1.
Evaluation was performed in the same manner as in Example 1 except that [Bk toner 1], [M toner 1], [C toner 1], and [Y toner 2] were used as toners. It was shown in 2.

Bead mill dispersion conditions of [Y pigment / wax dispersion] Liquid feeding speed: 1 Kg / hr, disk peripheral speed: 8 m / sec, number of passes: 2 times

Comparative Example 2
[Y toner 3] was obtained in the same manner as in Example 1 except that the bead mill dispersion conditions of [Y pigment / wax dispersion] in the oil phase adjustment described in Example 1 were changed as follows. It was.
The resulting surface colorant abundance ratio of the toner, the volume average particle diameter (Dv), Dv / Dn, the average circularity was as shown in Table 1.
Evaluation was performed in the same manner as in Example 1 except that [Bk toner 1], [M toner 1], [C toner 1], and [Y toner 3] were used as toners. It was shown in 2.

Bead mill dispersion conditions of [Y pigment / wax dispersion] Liquid feeding speed: 0.5 Kg / hr, disk peripheral speed: 14 m / sec, number of passes: 5 times

Comparative Example 3
The bead mill dispersion conditions of [M pigment / wax dispersion], [C pigment / wax dispersion] and [Y pigment / wax dispersion] in the oil phase adjustment described in Example 1 were changed as follows. Except for the above, [M Toner 2], [C Toner 2], and [Y Toner 4] were obtained in the same manner as Example 1.
The resulting surface colorant abundance ratio of the toner, the volume average particle diameter (Dv), Dv / Dn, the average circularity was as shown in Table 1.
Evaluation was performed in the same manner as in Example 1 except that [Bk toner 1], [M toner 2], [C toner 2], and [Y toner 4] were used as toners. It was shown in 2.

Bead mill dispersion conditions of [M pigment / wax dispersion] Feed speed: 0.5 Kg / hr, disk peripheral speed: 14 m / sec, number of passes: 3 times Bead mill dispersion conditions of [C pigment / wax dispersion] Feed speed : 1 Kg / hr, disk peripheral speed: 8 m / second, number of passes: 1 [Y pigment / wax dispersion] bead mill dispersion condition Liquid feed speed: 0.5 kg / hr, disk peripheral speed: 12 m / second, number of passes : 3 times

[Comparative Example 4]
Evaluation was performed in the same manner as in Example 1 except that the evaluation machine B was used as the evaluation machine. Table 2 shows the measured values and the evaluation results.

Example 2
[M Toner 3] was obtained in the same manner as in Example 1 except that the bead mill dispersion conditions of [M Pigment / Wax Dispersion] in the adjustment of the oil phase described in Example 1 were changed as follows. It was.
The resulting surface colorant abundance ratio of the toner, the volume average particle diameter (Dv), Dv / Dn, the average circularity was as shown in Table 1.
Evaluation was performed in the same manner as in Example 1 except that [Bk toner 1], [M toner 3], [C toner 2], and [Y toner 3] were used as toners. It was shown in 2.

Bead mill dispersion conditions for [M pigment / wax dispersion] Liquid feeding speed: 1 Kg / hr, disk peripheral speed: 8 m / sec, number of passes: 2 times

Example 3
Except that the bead mill dispersion conditions of [M pigment / wax dispersion] and [C pigment / wax dispersion] in the oil phase adjustment described in Example 1 were changed as follows, the same as in Example 1 Thus, [M toner 4] and [C toner 3] were obtained.
The resulting surface colorant abundance ratio of the toner, the volume average particle diameter (Dv), Dv / Dn, the average circularity was as shown in Table 1.
Evaluation was performed in the same manner as in Example 1 except that [Bk toner 1], [M toner 4], [C toner 3], and [Y toner 1] were used as toners. It was shown in 2.

Bead mill dispersion conditions for [M pigment / wax dispersion] Feed speed: 0.5 Kg / hr, disk peripheral speed: 10 m / sec, number of passes: 2 times Bead mill dispersion conditions for [C pigment / wax dispersion] Feed speed : 0.5Kg / hr, disc peripheral speed: 8m / sec, number of passes: 3 times

Example 4
The bead mill dispersion conditions of [M pigment / wax dispersion], [C pigment / wax dispersion], and [Y pigment / wax dispersion] in the adjustment of the oil phase described in Example 1 were changed as follows. In the preparation of the aqueous phase, 28 parts of a 3.0% aqueous solution of the polymer protective colloid carboxymethylcellulose (Serogen BSH, manufactured by Sanyo Chemical Industries) was added to the aqueous phase, and in the emulsification step, the TK homopolymer after addition of the aqueous phase was added. Example 1 except that the number of revolutions of the mixer and the stirring time were changed to 10,500 rotations and 10 minutes, and the aqueous medium dispersion was changed to quickly dilute with 2000 parts of pure water after the completion of stirring. Thus, [M toner 5], [C toner 4], and [Y toner 5] were obtained.
The resulting surface colorant abundance ratio of the toner, the volume average particle diameter (Dv), Dv / Dn, the average circularity was as shown in Table 1.
Evaluation was performed in the same manner as in Example 1 except that [Bk toner 1], [M toner 5], [C toner 4], and [Y toner 5] were used as toners. It was shown in 2.

Bead mill dispersion conditions for [M pigment / wax dispersion] Feed speed: 0.5 Kg / hr, disk peripheral speed: 10 m / sec, number of passes: 2 times Bead mill dispersion conditions for [C pigment / wax dispersion] Feed speed : 0.5 Kg / hr, disk peripheral speed: 8 m / second, number of passes: 3 times [Y pigment / wax dispersion] bead mill dispersion conditions Liquid feed speed: 0.5 Kg / hr, disk peripheral speed: 11 m / second, Number of passes: 3 times

Example 5
Evaluation is performed in the same manner as in Example 1 except that [Bk toner 1], [M toner 5], [C toner 4], and [Y toner 5] are used as toners, and an evaluation machine C is used as an evaluation machine. The measured values and the evaluation results are shown in Table 2.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus of the present invention. It is a schematic block diagram which shows the other example of the image forming apparatus of this invention. It is a schematic block diagram which shows the other example of the image forming apparatus of this invention. It is a schematic block diagram which shows the other example of the image forming apparatus of this invention. FIG. 2 is a schematic explanatory diagram of a surf fixing device. FIG. 2 is a schematic explanatory diagram of an IH fixing device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoconductor 2 Primary transfer means 3 Sheet conveyance belt 4 Intermediate transfer body 5 Secondary transfer means 6 Paper feed means 7 Fixing means 8 Photoconductor cleaning means 9 Intermediate transfer body cleaning means 10 Intermediate transfer bodies 14, 15, 16 Support rollers 17 Intermediate transfer member cleaning means 18 Image forming means 20 Tandem image forming apparatus 21 Exposure means 22 Secondary transfer means 23 Roller 24 Secondary transfer belt 25 Fixing means 26 Fixing belt 27 Pressure roller 28 Sheet reversing means 30 Document table 32 Contact glass 33 First traveling body 34 Second traveling body 35 Imaging lens 36 Reading sensor 42 Paper feed roller 43 Paper bank 44 Paper feed cassette 45 Separating roller 46 Paper feed path 47 Carriage roller 48 Paper feed path 49 Registration roller 50 Paper feed roller 51 Manual feed tray 52 Separating roller 53 Manual feed path 55 Switching claw 56 Output roller 57 Paper discharge tray 61 Developing means 62 Primary transfer means 63 Photoconductor cleaning means 64 Static elimination means 65 Developer on developing sleeve 68 Stir paddle 69 Partition plate 71 Toner density sensor 72 Developing sleeve 73 Doctor 75 Cleaning blade 76 Cleaning brush 77 Cleaning roller 78 Cleaning blade 79 Toner discharge auger 80 Drive device 101 Copying device main body 140 Photoconductor 160 Charging means 200 Feeding table 300 Scanner 400 Automatic document feeder (ADF)
s Sheet T Tandem type image forming apparatus 81 Heating roller 82 Fixing roller 82a Core metal 82b Elastic member 83 Heat resistant belt (toner heating medium)
84 Pressure roller 84a Core metal 84b Elastic member 85 Temperature detection means 86 Induction heating means 87 Excitation coil 88 Coil guide plate 89 Excitation coil core 90 Excitation coil core support member 91 Recording material

Claims (16)

After developing an electrostatic latent image formed sequentially with a plurality of full-color toners containing at least a binder resin and a colorant and forming the image, and transferring the formed image onto a recording medium A full-color image forming apparatus having fixing means for fixing the image on the recording medium, wherein the full-color toner having the highest surface colorant abundance ratio among the full-color toners formed so as to be superimposed on the recording medium is located upper, surface colorant abundance ratio, Ri 1.3 to 2.0 der, surface colorant abundance ratio of each color toner is, and wherein 0.9-2.0 der Rukoto A full-color image forming apparatus. Each of the plurality of full-color toners has a colorant content of 1 to 15% by weight. The full-color image forming apparatus according to claim 1. The colorant content of each of the plurality of full color toners is the same. 3. The full-color image forming apparatus according to 1 or 2. Full-color image forming apparatus according to any one of claims 1 to 3, wherein the toner high the most superficial colorant abundance ratio of the yellow toner. The full-color toner, yellow, magenta, consists cyan toner, each surface colorant abundance ratio (Py, Pm, Pc) is, according to claim 1, wherein the Py> Pm, a Py> Pc The full-color image forming apparatus according to any one of the above. The surface colorant abundance ratio Pm of the magenta toner is 1.2 to 1.7, the surface colorant abundance ratio Pc of the cyan toner is 1.0 to 1.7, and the surface of the yellow toner The full-color image forming apparatus according to claim 5 , wherein the colorant abundance ratios Py> Pm and Py> Pc. The most superficial colorant abundance ratio high toner colorants, azo pigments, or full-color image forming apparatus according to any one of claims 1 to 6, characterized in that a quinacridone pigment. Toner base particles of the toner, the organic solvent containing the toner material, were dispersed in an aqueous medium, any one of claims 1 to 7, characterized in that a toner obtained by removing the organic solvent The full-color image forming apparatus described in 1. The recording medium on which the unfixed image is formed is a fixing unit having a heating body having a heating element, a film in contact with the heating body, and a pressure member in pressure contact with the heating body through the film. , a full-color image forming apparatus according to any one of claims 1 to 8, characterized in that for heating and fixing the unfixed image is passed between the said film pressure member. The recording medium on which the unfixed image is formed is composed of a heating roller made of a magnetic metal and heated by electromagnetic induction, a fixing roller arranged in parallel with the heating roller, and the heating roller and the fixing roller. An endless belt-shaped toner heating medium stretched between and heated by the heating roller and rotated by these rollers, and pressed against the fixing roller via the toner heating medium, The fixing unit having a pressure roller that rotates in the forward direction with respect to the rotational movement direction to form a fixing nip portion passes between the toner heating medium and the pressure roller to heat the unfixed image. full-color image forming apparatus according to any one of claims 1 to 9, characterized in that the fixing. A recording medium after developing an electrostatic latent image formed sequentially with a plurality of full-color toners containing at least a binder resin and a colorant to form an image and transferring the formed image onto the recording medium A full-color image forming method for fixing an upper image, wherein among the full-color toners formed so as to be superimposed on the recording medium, the full-color toner having the highest surface colorant abundance ratio is in the upper layer, surface colorant abundance ratio, Ri 1.3 to 2.0 der, surface colorant abundance ratio of each full color toner, a full-color image formation, wherein 0.9-2.0 der Rukoto Method. Each of the plurality of full-color toners has a colorant content of 1 to 15% by weight. The full-color image forming apparatus according to claim 11. Claims that are each the same 11. The full color image forming method according to 11. The colorant content of each of the plurality of full color toners is the same. The full-color image forming method according to 11 or 12. The toner image formed by sequentially developing the electrostatic latent image formed on the electrostatic latent image carrier with a plurality of full-color toners containing at least a binder resin and a colorant is transferred onto a recording medium. Used in a fixing device for fixing a toner image on a recording medium after the toner image, and is a full-color toner kit composed of at least yellow, magenta, and cyan toners, and the toner image is formed so as to be superimposed on the recording medium. was among the full-color toner, the highest color toner surface colorant abundance ratio is in the upper layer, the surface colorant abundance ratio is 1.3 to 2.0 der is, there surface colorants for each color toner the amount ratio, full-color toner Kid, wherein 0.9 to 2.0 der Rukoto. Each of the plurality of full-color toners has a colorant content of 1 to 15% by weight. The full-color toner kit according to claim 15. The colorant content of each of the plurality of full color toners is the same. The full color toner kid according to 14 or 15.

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